The referent of "illa" in this passage?

Question

What is the referent of "illa" in the passage below from Simon Episcopius's Institutiones theologicae and how would it be translated?

Nec dicam operose de Theologiae, quas vocant, speciebus, in quas Theologiam analogice dividere quidam solent, videlicet de Archetypo & Ectypo, sive ut barbare quidam loquuntur, Archetypa & Ectypa; quarum illa Dei ipsius esse dicitur, qua se ipsum & omnia divina divino & ineffabili modo intelligit, ac proinde prorsus ακοινώνητος.

I will not speak elaborately about what certain men call the "kinds" of Theology, namely, about the Archetypal and Ectypal, into which they often divide theology analogically, or as certain men barbarously call them, Archetypal and Ectypal matters; the one of which is said to be of God as He knows Himself and all things divine by a heavenly and ineffable manner, and is hence altogether ακοινώνητος (incommunicable).

Answer 1

Ille...hic is a commonly correlated pair in Latin meaning "the former...the latter." The idea is that ille ("that") is the first thing mentioned--and thus further away--while hic is the last thing mentioned--and thus closer. See Allen & Greenough §297 for further details and complications.

In this case, your quote cuts off the second part of this correlated pair. The sentence continues as follows:

...ac proinde prorsus ακοινώνητος, haec expressa ad ideam illam & communicata tripliciter; per unionem hypostaticam; per visionem; per revelationem....

The illa in your quoted part refers to the former species of theology (de Archetypo), and the haec refers to the latter species (de Ectypo). They are both feminine singular to agree with species.